Improvement in molds for castings



UNITED STATES PATENT OFFICE.

JOHN R. DAVIS, OF RACINE, TISOONSI IMPROVEMENT IN MOLDS FOR CASTINGS.

.'sprcilcaton forming part oflicttcrs Patent No. 37.857, dated March l0,ISGS.

To all whom t may concern:

Be it known that I, `IoHN R. DAvis, of Ra cine, in the county of Racineand State of \Visconsin, have invented a new and useful Improvement inMolds for Castings; and I do hereby declare that the following is afull, clear, and, exact description of the same, reference being had tothe accompanying drawings, forming a part of this specification, inwhichp Figure l represents a vertical central section of my invention.Fig. 2 is a horizontal section ofthe same, the line m, Fig. l,indieating the plane of section.

Similar letters of reference in both views indica-tc correspondingparts.

The success of castings depends greatly on the skill of the melder, andin molding the operation of drawing the pattern or lifting it out of thesand constitutes one of the Inost important and difficult operations.The sand must be weted in order to give it the required compactness, andeven then, if the operation of drawing the pattern is not performed by askillful and steady hand, the edges of the cavities produced in the sandby the patterns are liable to break off, and a poor casting is theresult.

The object of this invention is to facilitate the operation of drawingthe pattern or patterns.

The invention consists in the arrangement of movable legs or pinsoperated by means of a screw and hinged levers, or by other suitablemeans, in combination with the matchboard and iiask, in such a mannerthat by the action of said legs or pins on the ask the pattern orpatterns secured to the match-board are raised up perfectly steady anddrawn from the sand with the greatest ease and facility.

To enable those skilled in the art to make and use my invention, I willproceed to describe it with reference to the drawings.

A represents the match-board, which forms the bottom of the ask B untilthe latter is rammed full of sand. This match-board is provided withguide-pins a, which fit into holes made in lugs b, that are secured tothe sides of the Ilask, so that when the two are placed together theirrelative position toward each other cannot be disturbed.

(l is a box made of wood or other suitable material, and attached to thematch-board, either rigidly or so that it can be easily re- Inoved. Thisbox is made of the same size as the match-board, and it contains ascrew, D, which is screwed into ametal plate, c, let into the innersurface of the match-board, and which has its bearing in a plate, d,that is secured to the inner surface of the top of the box C, and whichcatches into a circular neck turned into said screw close under itshead.

Said screw screws into an armed hub, E, the

arms of which extend in diagonal directions, and connect, by means ofpivots e, with levers F, which are fulcrumed 011 pivots f in slottedstandards G. These standards are se, cured by means of screws, or -inany other suitable manner, to the inner surface of the match-board, andthey are fastened to the top of the box C by screws and nuts or anyother desirable means. The levers F extend into the corners of the boxC, and theirouter ends are pivoted to pins or legs H, which pass freelythrough holes in the match-board. By the action of the screw D andlevers F the legs H are simultaneously drawn in or pushed out, and ifthe match-board rests on the flask and the screw is turned so as toraise the hub E the points of the legs are caused to bear on the edgesof the fiask and to raise up the matchboa-rd, as clearly shown in lFig.1 of the drawf ings.

It is obvious that the movable legs II, instead of being round pins,might be made of eccentric disks, or constructed in any other de sirablemanner, and instead of the screw and levers cog-wheels or any othersuitable device might be employed to operate said legs.

The pattern or patterns to be cast are fastened to the match-board,which is then placed under the flask, and the latter is rammed full ofsand.

The whole device, ilask and all, is then turned upside down, and byturning the screw D the match-board, with all the patterns attached toit, is raised up perfectly even and steady, and the patterns are drawnperfectly safe and without the least injury to the edges of the cavitiesleft by the patterns in thesand.

This improvement is of particular advandlage in casting small articles,and in this case a number of patterns are secured to the match-board,and by the action of the Inovable legs on the match-board and flask theseveral patterns are simultaneously` drawn out of the sand. The movablelegs and levers The application of movable legs H, operated by means ofa screw, D, and hinged levers F, or their equivalents, in combinationwith the match-board or pattern A and flask B, substantially as and forthe purpose herein shown and described.

JOHN DAVIS.

XVitnesses M. S. PARTRIDGE, DANIEL ,RoBERTsoN

